Year	Percent
1986	10
1987	10
1988	10
1989	10
1990	10
1991	10
1992	10
1993	10
1994	10
1995	10
1996	10
1997	10
1998	10
1999	7
2000	7
2001	7
2002	7
2003	5
2004	5
2005	5
2006	5